Focusing public attention on emerging privacy and civil liberties issues

Whole Body Imaging Technology ("Backscatter" X-Ray and Millimeter Wave Screening)

Top News

  • EPIC Sues Homeland Security for Information About Digital Strip Search Devices: EPIC filed a Freedom of Information Act lawsuit challenging the Department of Homeland Security's failure to make public details about the agency's Whole Body Imaging program. The devices capture detailed naked images of air travelers in the United States. After the agency announced that the body scanners would become the primary screening device in US airports, EPIC demanded that the agency disclose records that describe the scanners' capacity to save and transmit images. In June, EPIC sent a letter to the Secretary of Homeland Security Janet Napolitano urging her to suspend the digital strip searches. For more, see EPIC Backscatter X-ray, Whole Body Imaging and EPIC Air Travel Privacy. (Nov. 9, 2009)
  • Privacy Coalition Seeks Investigation of DHS Chief Privacy Office: EPIC joined the Privacy Coalition letter sent to the House Committee on Homeland Security urging them to investigate the Department of Homeland Security's (DHS) Chief Privacy Office. DHS is unrivaled in its authority to develop and deploy new systems of surveillance. The letter cited DHS use of Fusion Center, Whole Body Imaging, funding of CCTV Surveillance, and Suspicionless Electronic Border Searches as examples of where the agency is eroding privacy protections.  EPIC Fusion Centers, EPIC Whole Body Imaging, and EPIC CCTV. (Oct. 23, 2009)
  • TSA Expands Passenger Electronic Strip Search Program: The Transportation Security Administration (TSA) has plans to greatly expand its use of whole body imaging machines at airports around the country. The x-ray machines, which each cost over $100,000, capture detailed, graphic images of passengers' naked bodies. In June, the House of Representatives overwhelmingly passed a measure that would restrict TSA's use of these machines. The measure is pending in the Senate. The Privacy Coalition has urged the Department of Homeland Security to suspend the program until privacy and security risks can be fully evaluated. EPIC has also filed Freedom of Information Act requests for the contracts with the vendor Rapiscan. For more information, see EPIC Whole Body Imaging Technology and EPIC Spotlight on Surveillance. (Oct. 6, 2009)
  • TSA Responds to Whole Body Imaging Objections: The Transportation Security Administration has replied to the Privacy Coalition statement on whole body imaging systems. The agency claims that the Privacy Impact Assessment (PIA) provides adequate protection. The Privacy Coalition letter pointed out that "the devices are designed to capture, record, and store detailed images of individuals undressed" and said that "If the public understood this, they would be outraged by the use of these devices by the US government on US citizens." The Privacy Coalition said that the use of the devices should be suspended pending an investigation. The letter was prompted by the TSA's announcement that Whole Body Imaging would replace metal detectors as the primary screening technique at US airports. The House of Representatives recently passed legislation that would establish clear privacy safeguards for the devices. See also EPIC's page on Whole Body Imaging. (Jun. 23, 2009)
  • Congress Approves Bill Limiting TSA's Use of Whole-Body Imaging: Today, the House approved a bill that will limit the use of Whole-Body Imaging machines, installed by the Transportation Security Administration, in US airports. The devices photograph American air travelers stripped naked and could easily be programmed to record images. Congressman Jason Chaffetz (R-UT) sponsored the bill that will prohibit the use of the devices as the sole or primary method of screening aircraft passengers; require that passengers be provided information on the operation of such technology and offered a pat-down search in lieu of such screening; and prohibit the storage of an image of a passenger after a boarding determination is made. EPIC launched a campaign and a Facebook Group seeking to raise public awareness about Whole Body Imaging. See EPIC's Backscatter X-ray, Whole Body Imaging, and Air Travel Privacy pages. (Jun. 4, 2009)
  • EPIC Urges Homeland Security to Stop Digital Strip-Searches: EPIC sent a letter to the Secretary of Homeland Security, Janet Napolitano, urging the suspension of the Whole Body Imaging program. The devices would capture detailed naked images of all passengers at US airports. EPIC and thirty organizations asked Napolitano to begin a formal rulemaking and investigate less invasive means of screening. EPIC has also launched a campaign and established a Facebook Group to stop the program. See EPIC's Backscatter X-ray, Whole Body Imaging, and Air Travel Privacy pages. (Jun. 2, 2009)
  • EPIC Launches Campaign to Suspend 'Whole Body Imaging' at Nation's Airports: EPIC announced a national campaign today to suspend the use of "Whole Body Imaging" -- devices that photograph American air travellers stripped naked in US airports. The campaign responds to a policy reversal by the TSA which would now make the the "virtual strip search" mandatory, instead of voluntary as originally announced. EPIC and others say that there are inadequate safeguards to prevent the misuse of the images. They are asking Homeland Security Secretary Janet Napolitano to suspend the program and to allow for public comment. For more information, see EPIC's Backscatter X-ray, Whole Body Imaging page. (May. 18, 2009)
  • Congressman Seeks Ban on Whole-Body Imaging at Airports: Congressman Jason Chaffetz has introduced legislation seeking a ban on Whole-Body Imaging machines installed by the Transportation Security Administration in various airports across America. Describing the method as unnecessary to securing an airplane, Congressman Chaffetz stated that the new law was to "balance the dual virtues of safety and privacy." The TSA recently announced plans to make the scanners, which capture a detailed picture of travelers stripped naked, the default screening device at all airport security checkpoints. For more information, see EPIC's Whole Body Imaging page. (Apr. 24, 2009)
  • EPIC Demands Disclosure of Documents Detailing "Virtual Strip Search" Airport Scanners: Today, EPIC filed a Freedom of Information Act request demanding disclosure of records detailing airport scanners that take naked pictures of American travelers. Security experts describe the "whole body imaging" scanners as virtual strip searches. The Transportation Security Administration plans to make the scans mandatory at all airport security checkpoints, despite prior assurances that whole body imaging would be optional. EPIC's request seeks documents concerning the agency's ability to store and transmit detailed images of naked U.S. citizens. For more information, see EPIC's Whole Body Imaging page and EPIC's FOIA Litigation Manual. (Apr. 14, 2009)
  • TSA Broadens Use of 'Backscatter X-Ray' Machines That Conduct 'Virtual Strip Searches': The Transportation Security Administration is expanding the use of "backscatter X-ray" systems for passenger screening. The $100,000 refrigerator-size machines use "backscatter" technology, which bounces low-radiation X-rays off of a passenger to produce photo-quality images of travelers as if they were undressed. Computer processing partially obscures the image that is available to operators. TSA states that the agency will delete the raw images, but there is no law or regulation that prevents the agency from saving the original, detailed images. Until there is such a prohibition, EPIC believes funding for the program should be suspended. See EPIC's Spotlight on Surveillance and page on Backscatter X-ray. (October 11, 2007)
  • Field Tests Begin in Arizona on Backscatter X-Ray Machines: An X-ray machine aimed at detecting weapons and explosives hidden on passengers is scheduled to make its debut Friday at Phoenix's Sky Harbor International Airport. The "backscatter" will be in operation at Security Checkpoint B in Terminal 4. While any Terminal 4 ticketed passenger can pass through any checkpoint, the B concourse is primarily used by travelers on Tempe-based US Airways. (February 21, 2007)
  • Phoenix Airport to Use 'Backscatter' X-Ray on Travelers: Sky Harbor International Airport here will test a new federal screening system that takes X-rays of passenger's bodies to detect concealed explosives and other weapons. The technology, called backscatter, has been around for several years but has not been widely used in the U.S. as an anti-terrorism tool because of privacy concerns. (December 1, 2006)

Background

Post-September 11, airline travel security has invoked the increased use of technology and better training of security personnel as a means of improving travel security. Some of these proposals, such as improved training for airport screeners, checking all bags for bombs, strengthening cockpit doors, and placing air marshals on flights, do not implicate privacy interests and are sound security measures. Others, however, present privacy and security risks to air travelers because they might create data files directly linked to the identity of air travelers. These files if retained could provide the basis for a database of air traveler profiles. The Transportation Security Administration utilizes two technologies to capture naked images of air travelers - backscatter x-ray technology and millimeter wave technology.

In 1895 x-rays1 were discovered by Wilhelm Röntgen.2 This discovery of how to look through an object to observe details beneath has advanced to include new techniques. One such technique called "backscatter" X-Ray is based on "the emergence of radiation from that surface of a material through which it entered. Also used to denote the actual backscattered radiation.3"

backscatter imageThe application of this new x-ray technology to airport screening uses high energy x-rays that are more likely to scatter than penetrate materials as compared to lower-energy x-rays used in medical applications. Although this type of x-ray is said to be harmless it can move through other materials, such as clothing.

A passenger is scanned by rastering or moving a single high energy x-ray beam rapidly over their form. The signal strength of detected backscattered x-rays from a known position then allows a highly realistic image to be reconstructed. Since only Compton scattered x-rays4 are used, the registered image is mainly that of the surface of the object/person being imaged. In the case of airline passenger screening it is her nude form. The image resolution of the technology is high, so details of the human form of airline passengers present privacy challenges.

Airport security has undergone significant changes since the terrorist attacks of Sept. 11, 2001. Recently, the Transportation Security Administration (TSA) announced a proposal to purchase and deploy "Whole Body Imaging" X-ray machines to search air travelers at all airports. TSA said it believes that use of the machines is less invasive than pat-down searches. However, these machines, which show detailed images of a person's naked body, are equivalent to a "virtual strip search" for all air travelers. This proposal, along with the agency's controversial plan to profile air travelers, shows extraordinary disregard for the privacy rights of air travelers. The Department of Homeland Security is requesting $72 million to invest in detection systems, which includes funding for the backscatter machines, which cost between $100,000 and $200,000 each.

The backscatter machines use high-energy X-rays that are more likely to scatter than penetrate materials as compared to lower-energy X-rays used in medical applications. Although this type of X-ray is said to be harmless, it can move through other materials, such as clothing. When being screened, a passenger is scanned by high-energy X-ray beam moving rapidly over her body. The signal strength of detected backscattered X-rays from a known position then allows a highly realistic image to be reconstructed. In the case of airline-passenger screening, the image is of the traveler's nude form. The image resolution of the technology is high, so the picture of the body presented to screeners is detailed enough to show genitalia. These images are not necessarily temporary - screeners can save the body images to the system's hard disk or floppy disk for subsequent viewing on either "the system monitor or on any IBM compatible personal computer with color graphics."

Backscatter X-Rays and Transportation Screening

The Transportation Security Administration claims that is not storing detailed images of passengers screened by the system. The agency also states that it is providing a screening option for passengers who object to screening by the technology. However, the technology is designed to accomplish what has been described on this page, and until the process of assuring that the claims of the agency are enforced--questions will remain about the use of the technology. EPIC will make available on this page aviation security and privacy -related documents it obtains from the government under the Freedom of Information Act law about the adoption of "backscatter" x-ray technology intended for use in screening air travelers.

womanThe stated goal of these new proposals is to rely on technology to reduce the "hassle factor" in airports and to reduce security threats. The core idea is to focus security resources on suspicious travelers, while ensuring that most people are not inconvenienced by heightened security. Terrorists, however, have been known to go to great lengths to look like most people. Will a technology that will capture detailed images of potentially all airline travel passengers lead to greater safety? Current technology can successfully detect dangerous substances, firearms and other weapons without backscatter x-ray imaging of passengers. Can the goal of safe air travel be reached without reproducing a digital image of a passenger's body? It has long been recognized by security experts that it is impossible to eliminate all threats to airline travel. Is the application of "backscatter" x-ray technology a deterrent and not a solution to perfect airline travel safety? If this is true, then is the trade off in passenger privacy worth the effort to deter terrorists? The application of security technology and increased passenger screening has also resulted in an increased detection of non-violent criminal offenses. Is the application of "backscatter" x-ray technology to screen airline passengers more than just a means of detecting terrorists?

In 2009, the TSA announced that Whole Body Imaging would replace metal detectors at airport security check points. This is a marked departure from the earlier promises by the agency that the technology would only be used for secondary screening of air travel passengers.

Airports Currently Using Whole Body Imagaing Technology

  • Albuquerque International Sunport Airport
  • Hartsfield-Jackson Atlanta International Airport
  • Baltimore/Washington International Thurgood Marshall Airport
  • Ronald Reagan Washington National Airport
  • Denver International Airport
  • Dallas/Fort Worth International Airport
  • Detroit Metro Airport
  • Indianapolis International Airport
  • Jacksonville International Airport
  • McCarran International Airport
  • Los Angeles International Airport
  • Miami International Airport
  • Phoenix Sky Harbor International Airport
  • Raleigh-Durham International Airport
  • Richmond International Airport
  • San Francisco International Airport
  • Salt Lake City International Airport
  • Tampa International Airport
  • Tulsa International Airport

Latest News

Resources

Identification Schemes

Profiling

Other Documents

Analysis

  • Paper on the limitations of profiling, Roger Clark, Australia National University.
  • ACLU testimony before White House Commission on "Civil Liberties Implications of Airport Security Measures" (September 5, 1996).
  • Letter to Privacy Journal editor Robert Ellis Smith from the FAA denying Smith's request for a copy of the FAA Security Directive on identification of airline passengers.
  • HotWired article "Fear of Flying" on proposals. (September 11, 1996).

Other Airline Passenger Screening Resources

  • FAA Proposes Profiling Regulations. The Federal Aviation Administration published proposed regulations on April 19, 1999, governing "Security of Checked Baggage on Flights Within the United States." The draft rules detail the use of computer profiling techniques to identify suspicious passengers.
  • Airline Passenger Profiling Goes Into Effect. The Computer Assisted Passenger Screening System was scheduled to be phased in nationwide beginning on January 1. Under the system, passengers who "fit the profile" will be selected for heightened security measures, which can include a thorough search of their luggage, intrusive personal questioning, tagging of luggage with orange tape, and a physical escort from the check-in counter to the airport gate by security personnel. The ACLU is providing an online complaint form for passengers targeted by the profiling system.
  • Microsoft Chief Architect Charles Simonyi tells what happens when you "fit the profile" (from Slate).
  • Proposed FAA rule for collecting personal information including name, address, Social Security Number, Date of birth and next of kin for every domestic passenger.
  • General Account Office report, Aviation Safety and Security: Challenges to Implementing the Recommendations of the White House Commission on Aviation Safety and Security (Testimony, 03/05/97, GAO/T-RCED-97-90).
  • The Gore Commission has released its final report recommending passenger profiling. A coalition of 17 groups has sent a letter to Gore opposing ID checks, profiling, new x-ray technologies and excessive secrecy by the FAA in making decisions.

Legislative History

HR 1271. FAA Research, Engineering, and Development Authorization Act of 1997. Funds FAA projects for new surveillance technologies such as advanced x-ray systems for individuals. Introduced on 4/10/97 by Morella (R-Md). Referred to the House Committee on Science. Approved by Committee 4/16/97. Reported to the House H. Rept. 105-61 (CR H1714) on 4/21/97. Measure adopted on 4/29/97, RC #95 (414-7), (CR H1995). Referred to Senate Committee on Commerce, Science and Transportation (CR S3843) on 4/30/97.

Bill Passed the Senate: 11/13/1997
Mr. Sensenbrenner moved that the House suspend the rules and agree to the Senate amendments: 2/3/1998
Bill Passed the House by a voice vote: 2/3/1998 3:07pm:
Bill Signed into Law by President Clinton: 2/11/1998
Became Public Law No: 105-155.

References

1http://hyperphysics.phy-astr.gsu.edu/hbase/ems3.html#c4
2http://geology.b.dictonarypage.co.uk/backscatter/
3http://www.absoluteastronomy.com/encyclopedia/X/X/X-Ray_machine.htm
4http://hyperphysics.phy-astr.gsu.edu/hbase/quantum/comptint.html